Because this is an addition problem, we will be finding the sum.
16 + 3.6 + 4.049
We can add 3.6 to 4.049 as none of the digits will overlap except 3 and 4, which we can add together to make 7.
3.6 + 4.049 = 7.649
Now the problem is 16 + 7.649
Adding these two together gives us 23.649.
Your answer is 23.649